5661610665566 has 16 divisors (see below), whose sum is σ = 8939645827200. Its totient is φ = 2681737408728.

The previous prime is 5661610665563. The next prime is 5661610665593. The reversal of 5661610665566 is 6655660161665.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5661610665563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 839936 + ... + 3468243.

It is an arithmetic number, because the mean of its divisors is an integer number (558727864200).

Almost surely, 2^{5661610665566} is an apocalyptic number.

5661610665566 is a deficient number, since it is larger than the sum of its proper divisors (3278035161634).

5661610665566 is a wasteful number, since it uses less digits than its factorization.

5661610665566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4342783.

The product of its (nonzero) digits is 34992000, while the sum is 59.

The spelling of 5661610665566 in words is "five trillion, six hundred sixty-one billion, six hundred ten million, six hundred sixty-five thousand, five hundred sixty-six".